Interventional cardiology works with numerous types of guidewires, sheaths and catheters for providing cardiac assessment and therapy. For example, electrophysiology catheters are used in a variety of diagnostic, therapeutic, and/or mapping and ablative cardiology procedures to diagnose and/or correct conditions such as atrial arrhythmias, including for example, ectopic atrial tachycardia, atrial fibrillation, and atrial flutter. Arrhythmias can create a variety of conditions including irregular heart rates, loss of synchronous atrioventricular contractions, and stasis of blood flow in a chamber of a heart, which can lead to a variety of symptomatic and asymptomatic ailments and even death. Balloon catheters are also widely used in interventional cardiology for numerous treatments.
Typically, a catheter or catheter sheath is deployed and manipulated through a patient's vasculature to the intended site, for example, a site within a patient's heart. In many cases, the catheter or catheter sheath is used in combination with a leading guidewire so as to allow easier and safer access to the intended site. The guidewire may first be introduced into the vasculature to the intended site and then the catheter threaded over the guidewire to the site. In order to improve the overall procedure and outcome, it is desirable for an operator to know the position and orientation of the catheter, and specifically the tip of the catheter, and then to visualize the guidewire as it is navigated within the body of the patient in order to minimize physical injury to the tissues surrounding the desired organ and ensure that the guidewire reaches its intended target. Some general methods for determining the position and orientation of medical devices using fluoropaque markers such as a metallic coil and/or an active impedance-sensing electrode are known in the art. Improving these known methods may provide improved reliability and patient outcomes.